The contribution of tax revenues to Gross Domestic Product (GDP) is lower in African and other developing countries between (16-18%) and developed countries (33%). Only African countries' revenues from duties and taxes on international trade exceed those of OECD member countries as a percentage of GDP.

The 2020 report of the United Nations Conference on Trade (UNCTAD) on illicit financial flows and sustainable development in Africa, particularly illicit revenues and financial flows, show that corporate tax avoidance mechanisms are causing a considerable loss of revenue. Thus, according to the report, developing countries lose a greater share of their tax revenues in this way than developed countries; yet as a percentage of Gross Domestic Product (GDP), their corporate tax revenues are already almost equivalent. As a result, one might expect an increase in the amount of corporate tax revenues, given that "common law rates are generally higher in developing countries, but the effective rates are sometimes lower than the rates of ordinary law, due to tax incentives," the report notes. In any event, given the diverse composition of the tax base in developing countries, it will be possible "to significantly increase the amount of total tax revenue only at the prices of interventions on their various sources, including, but not just corporate tax," the trade experts argue. ILLICIT FINANCIAL FLOWS AND TAX REVENUES According to the report, "overall capital flight and estimated losses resulting from tax evasion are presented by region and differ from region to region. On average, losses due to tax evasion are higher in Central, North and East Africa (2.7% of GDP), than in Southern Africa (about 2% of GDP) and West Africa (2.3% of GDP)." The median rate of capital flight, expressed as a percentage of GDP, ranges from 2.7 per cent in North Africa to 10.3 per cent in West Africa. Experts argue that "when capital flight is high, tax revenues decrease." For these to increase, it is necessary in particular that "the legal provisions are applied and that the administrative capacity for recovery is sufficient".13% OF DIFFERENCE BETWEEN THE RECOVERABLE AND THE RECOVERED In the case of value added tax, the tax gap, that is, the difference between the amount recoverable and the amount recovered, can vary greatly between countries. It thus extends from 13% in South Africa to 92% in the Central African Republic (Uneca, 2019). This is due to special provisions or derogations from the laws governing value added tax, or to problems with the management of collection, including problems with the efficiency, capacity, fraud or reliability of consumption data. Studies by Coulibaly and Gandhi, carried out in 2018, estimate that by improving tax efficiency and reducing the tax gap, estimated at 20% on average, it would be possible to increase the tax revenue/GDP ratio by 3.9%.110 BILLION DOLLARS TO BE RECOVERED EVERY YEAR Convinced that there is still room for manoeuvre Working to absorb the considerable losses, UNCTAD evaluators argue that "better control of corruption and effective enforcement of existing laws could largely remedy the situation and contribute to the recovery of an additional $110 billion per year." In total, capital flight amounted to about $88.6 billion per year in 2013-2015. According to the experts' analysis, "the contribution of tax revenues to GDP is lower in African and other developing countries than in developed countries (33%)". Only African countries' revenues from international trade duties and taxes exceed those of organisation for economic co-operation and development (OECD) member countries as a percentage of GDP. The report states that 'the recovery rate is limited by the size of the informal sector and the large number of small enterprises'. In addition, a tax system favouring multinational enterprises that exploit natural resources and pay taxes in the countries where they are headquartered leads to a narrowing of the tax base, particularly in countries dependent on natural resources. Jean Pierre Malou

South Daily